Massively: Terry Pratchett is coming to visit Second Life. Go back and read that again. Yes, it's true.
While Pratchett's Discworld series alone has sold 55 million globally in 35 countries, you'll probably not find a single, larger concentration of fans of his work than in Linden Lab's Second Life. Indeed, the virtual environment already has cadres of role-players, recreations of various Discworld settings, and Discworld-themed merchandise.
Sometime on Thursday 11 September (UK time) an island called "The Nation" (not yet visible within Second Life -- though heaven knows, we looked for it) is supposed to open for one month, until Friday 10 October.